The embodiments described herein relate generally to electrical machines, and more particularly, to methods and systems for coupling a motor and a gearbox together within a housing of the electrical machines.
Certain electrical machines are sometimes referred to as brushless motors. Brushless motors include both brushless AC motors and brushless DC motors and are used in a wide variety of systems operating in a wide variety of industries. Motors commonly include a stator and a rotor with each having a plurality of stacked laminations and a central bore for receiving a rotating shaft. A housing encloses the motor and the electronics that control the motor. The housing includes a pair of end frames or end caps which are coupled to opposite ends of the stator to facilitate supporting the rotor. Proper radial and axial alignment among the motor components is desired to facilitate providing free rotation of the shaft for a variety of speeds and torques.
To provide speed and torque for a given application, some electrical machines may couple the motor to a gearbox which includes the necessary gear ratio to deliver the required speed and torque from an input shaft to an output shaft. This application, however, may require numerous sizes of motors and numerous sizes of gearboxes to cover a variety of speed and torque ranges. Multiple gearbox assemblies may lead to increased inventory costs, operating costs, maintenance costs and/or replacement costs. In some electrical machines, coupling the gearbox to the input shaft and to the output shaft may increase the size and axial length of the electrical machine. Increasing the size, however, could result in space constraint issues and in increased manufacturing costs, operating costs, maintenance costs and/or replacement costs.
Moreover, if not properly dissipated, heat generated by electronics and/or other components during operation of the electrical machine can shorten the life span of various electronics and/or motor components and/or generally result in poor performance of the electrical machine. Some electrical machines couple a cooling fan to the input shaft for heat dissipation. The fan, however, in combination with conventional gearboxes may also increase the size of the electrical machine.